Abstract: Considering the "time and space effect" of deep excavations in soft soil area is significant,based on excavations case in Hexi area,Nanjing,the mechanism of large deformation of excavations under deep soft soil is analyzed.Comprehensive control measures such as supporting reinforcement,load limiting,unloading,isolation piles,reinforcement and thickening cushion,and floor construction are adopted,the deformation rate of excavations is effective controlled,which guarantees the evcavations to be carried out safely and smoothly.It provides reference for deformation control of excavations engineering in similar soft soil area.